In a known invert mechanism of this type, as shown in Italian patent publication IT 1 247 203 B, FIG. 2, the electric servomotor is mounted with its vertical longitudinal axis below the cover plate of the box in a housing. The electric servomotor drives a coaxial shaft which has a screw at the top. The screw is engaged with a worm wheel attached to the invert shaft. This construction method is costly, involves large rotating masses and takes up valuable space in the box.
It is known per se from German Patent Publication. DE 195 17 281 C1 to mount the two guide sleeves directly on the invert shaft. The axial opening and closing movements of the guide sleeves are not synchronized with each other.
It is known per se from U.S. Pat. No. 3,445,218 to attach a toothed rack to each half of the neck mold holder. The toothed racks extend, in parallel with and spaced apart from each other, in parallel with the opening and closing direction of the neck mold holder halves. The space is bridged by a pinion which can be rotationally driven in a reciprocating manner and which is engaged with both toothed racks. In this way, at a high construction cost and with large space requirements, synchronization of the opening and closing movements of the neck mold holder halves is achieved.
It is known per se from German Patent Publication DE 35 27 758 C2 to drive the invert shaft in a reciprocating manner by a motor, wherein a direct current motor is preferably used, which is connected directly to the invert shaft and carries out less than one rotation for each movement of the invert arm between its two end positions (column 2, lines 57 to 63). A control circuit for the rotational movement of the invert shaft is disclosed.